The empirical formula : MnO₂.
<h3>Further explanation</h3>
Given
632mg of manganese(Mn) = 0.632 g
368mg of oxygen(O) = 0.368 g
M Mn = 55
M O = 16
Required
The empirical formula
Solution
You didn't include the pictures, but the steps for finding the empirical formula are generally the same
- Find mol(mass : atomic mass)
Mn : 0.632 : 55 = 0.0115
O : 0.368 : 16 =0.023
- Divide by the smallest mol(Mn=0.0115)
Mn : O =

The empirical formula : MnO₂
Answer : The Lewis-dot structure of
is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that rubidium has '1' valence electrons, iodine has '7' valence electrons and oxygen has '6' valence electrons.
Therefore, the total number of valence electrons in
= 1 + 7 + 2(6) = 20
As we know that
is an ionic compound because it is formed by the transfer of electron takes place from metal to non-metal element.
+2, because the element has more protons than electrons now
The last step in performing a titration is <span>determining the concentration of an unknown base. So the answer to your question is letter B. The concentration maybe either an acid or base. The other choices are the earlier procedures in performing titration.</span>